Lesson A2 - Evidence of climate change
The students learn about the greenhouse effect by building a greenhouse as an analogy with greenhouse gases in the atmosphere.
All objects emit infrared radiation; the warmer they are, the more infrared radiation they emit.
When the Earth’s surface is warmed by the sun, it emits infrared radiation.
The greenhouse gases in the Earth’s atmosphere absorb infrared radiation emitted by Earth’s surface. Only part of this infrared radiation escapes into space and the rest is sent back to the surface.
An increase in greenhouse gas concentration results in an increase in Earth’s surface temperature.